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在吉林省大安地区选取3个30m长的截面,探讨了松嫩平原西部苏打盐渍土发展规律。结果表明:松嫩平原西部的植被对土壤盐渍化发生和演化具有举足轻重的作用。植被一旦被破坏,在相距3-5m的微域尺度内地势相对高差很小(相对高差为2-18cm),土壤剖面间的性质与结构却存在明显的差异,甚至局部地下水的化学特征也发生巨大的变化。植被破坏后,土壤表层的粘粒逐渐向下迁移和淀积,致使土壤结构恶化,同时盐分表聚使土壤由盐分含量较低、碱化程度较弱的盐化草甸土迅速向碱化度较重的浅位柱状碱土和白盖苏打碱土转化,最后发展成为成片的白盖苏打碱土,最终使整个区域的盐渍化程度不断加重。人类不合理利用是近年来松嫩平原盐渍化迅速发展的重要原因;保护已有的植被和恢复被人类破坏的植被对遏制盐渍化的发展具有十分重要的意义。
Three 30m long sections were selected in Da’an area of Jilin Province to discuss the development of soda saline soil in western Songnen Plain. The results show that the vegetation in the western Songnen Plain plays an important role in the occurrence and evolution of soil salinization. Once the vegetation is destroyed, the relative elevation difference is very small (relative elevation is 2-18cm) in the micro-scale within 3-5m, there are obvious differences in the nature and structure of the soil profile, and even the chemical features of local groundwater Huge changes have taken place. After the vegetation is damaged, the clay particles on the surface of the soil gradually migrate downward and deposit, causing the soil structure to deteriorate. At the same time, the salinity table agglomerates the soil from salinized meadows with lower salinity and alkalinity to alkalize The heavier shallow columnar alkaline earth and the white-cap soda ash converted into sheet-forming white-cap soda ash, eventually increasing the salinization of the entire area. The irrational use of mankind is an important reason for the rapid development of salinization in the Songnen Plain in recent years. It is of great significance to protect the existing vegetation and to restore vegetation destroyed by human beings to curb the development of salinization.